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U. S. ENVIRONMENTAL PROTECTION AGENCY

Washington, D.C. 20460

OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION

PC Code: 067710

DP Barcode: 402100

MEMORANDUM November 6, 2012

SUBJECT: Tier II Drinking Water Assessment for the New Use Registration of 

Indoxacarb on Dry Beans, Snap Beans, Small Fruit Vine Climbing Subgroup 

13-07F and Low-Growing Berry Subgroup 13-07H.

TO: Laura Nollen, Risk Manager Reviewer

Barbara Madden, Risk Manager

Registration Division (7505P)

Mike Metzger

Risk Assessment Branch 5

Health Effects Division (7509P)

FROM: Christopher M. Koper, Chemist

Environmental Fate and Effects Division (7507P)

THROUGH: He Zhong, Ph.D., Biologist

Sujatha Sankula, Ph.D., Lead Biologist

Ed Odenkirchen, Ph.D., Acting Branch Chief

Environmental Fate and Effects Division (7507P)
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1. EXECUTIVE SUMMARY

A Tier II screening-level drinking water assessment was conducted to support the human health risk 

assessment for the proposed new use registration for indoxacarb. Modeled application rates represent the 

maximum application rates from the proposed labels (DuPont TM Avaunt®, EPA Reg. No. 352-597 and 

DuPont TM Steward® EC, EPA Reg. No. 352-638) for use on dry beans, snap beans, small fruit vine 

climbing subgroup 13-07F and low-growing berry subgroup 13-07H. For dry and snap beans and the 

low-growing berry subgroup, the proposed maximum application rate is 0.44 lbs. a.i./acre (4 applications 

at 0.11 lbs. a.i./acre). For cranberry and the small fruit vine climbing subgroup, the proposed maximum 

application rate is 0.22 lbs. a.i./acre (2 applications at 0.11 lbs. a.i./acre). In addition, aerial and ground 

foliar spray applications and chemigation techniques are the proposed application methods. 

Blockage of the neuronal sodium channel produces the insecticidal mode of action of indoxacarb. The 

insecticidal activity of the compound is believed to be attributed to the rapid and extensive conversion of 

indoxacarb in insects to a more active metabolite (IN-JT333). In insects, IN-JT333 has greater affinity for 

the sodium channel complex compared to the parent compound. Indoxacarb exists as an isomer pair 

taking form as the active (S) isomer and inactive (R) isomer. The major routes of degradation of

indoxacarb include alkaline-catalyzed hydrolysis, photodegradation in water, and microbial mediated 

degradation. 

A cumulative residue modeling approach was used to account for the environmental fate and transport of 

indoxacarb plus degradation products with toxicological concern (IN-JT333, IN-KG4333, IN-KT413, INML437-0H) (USEPA 2000). The Metabolism Assessment Review Committee (MARC) of the Health 

Effects Division (HED) reviewed the degradate structures to determine residues of concern. Based on the 

MARC memorandum, a Total Toxic Residue (TTR) approach (Table 1) should be applied for the parent 

indoxacarb and the degradation products with toxicological concern (IN-JT333, IN-KG4333, IN- KT413, 

IN-ML437-0H) for the drinking water assessment. 

Table 1. Total Toxic Residue (TTR) Expression

Matrix: Residues of Concern: Structure:

Drinking Water Indoxacarb

((S) active isomer)

N N

O

Cl

O

N

O

CH3

O

O

F

F F

O

O

CH3

IN-JT333
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Table 1. Total Toxic Residue (TTR) Expression

Matrix: Residues of Concern: Structure:

IN-KG4333

IN-KT413

IN-ML437-0H

Based on MARC decision memorandum (D267726)

The recommended estimated drinking water concentrations (EDWCs) for the human health riskassessment are based on highest predicted value for surface water and groundwater (Table 2), which are 

based on two applications of 0.11 lbs. a.i./acre/season on cranberry and four applications of 0.11 lbs. 

a.i./acre on beans and berries respectively.

Table 2. Recommended Estimated Drinking Water Concentrations (EDWCs)1for Surface Water 

and Ground Water 

Drinking 

Water 

Source

Model

Scenario Method2

Maximum 

Application Rate

(interval between 

applications)

1-in-10 

year 

acute 

(μg/L)

1-in-10 

year 

chronic 

(μg/L)

30- year 

average 

(μg/L)

Surface 

Water

Provisional Cranberry Model

Cranberry PCM 2 app @ 0.11 lb a.i./acre 59.26 18.48 18.48

Ground 

Water

SCI-GROW

(Beans, Berries) -- 4 app @ 0.11 lb a.i./acre 0.33 0.33 0.33
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Table 2. Recommended Estimated Drinking Water Concentrations (EDWCs)1for Surface Water 

and Ground Water 

Drinking 

Water 

Source

Model

Scenario Method2

Maximum 

Application Rate

(interval between 

applications)

1-in-10 

year 

acute 

(μg/L)

1-in-10 

year 

chronic 

(μg/L)

30- year 

average 

(μg/L)

1 For surface water (PRZM/EXAMS), EDWC values adjusted with a Percent Cropped Area (PCA) factor of 0.87. 

For ground water (SCI-GROW), no PCA adjustment was utilized. 

2 PCM = The Provisional Cranberry Model (PCM) is a provisional refinement to the Tier I Rice Model (v1.0, May 8, 

2007). Refinements include the addition of simple degradation processes in dry and flooded conditions and a water 

depth of twelve inches, rather than the water depth of four inches used in the rice model. These modifications allow 

estimation of screening-level peak and annual mean EDWCs of residues of concern that may occur in untreated 

surface water used as drinking water following use on cranberries.

2. PROBLEM FORMULATION

A Tier II drinking water assessment (DWA) utilized modeling to estimate the surface water and 

groundwater concentrations of indoxacarb in drinking water source water (pre-treatment) resulting from 

use on vulnerable sites. No monitoring data are available for indoxacarb at the time of this assessment.

While Tier I DWAs are designed to screen out chemicals with low potential risk for posing a drinking 

water concern, the Tier II assessment provides more site-specific, refined modeling estimates of exposure 

by using additional environmental fate parameters, specific soil data, weather information, and 

management practices to estimate daily concentrations for an extended period of time (up to 30 years). 

This Tier II surface water assessment reflects application of indoxacarb at the maximum label rate and 

with scenarios intended to be representative of an environment that is more vulnerable to runoff and 

leaching than where most of the assessed commodities may be present.

2.1. Background

Indoxacarb insecticidal mode of action is the blockage of the insect’s neuronal sodium channels. The 

insecticidal activity of the compound is believed to be attributed to the rapid and extensive conversion of 

indoxacarb to a more active metabolite (IN-JT333). In insects, IN-JT333 has greater affinity for the 

sodium channel complex compared to the parent compound. Indoxacarb was initially registered in 

October 2000 for control of certain lepidopteran pests including beat army worm and is also considered 

an organophosphate (OP) replacement. 

2.2. Use Characterization

The registrant is seeking new use registration on dry beans, snap beans, small fruit vine climbing 

subgroup 13-07F and low-growing berry subgroup 13-07H. For dry and snap beans and the low-growing

berry subgroup, the proposed maximum application rate is 0.44 lbs. a.i./acre (4 applications at 0.11 lbs. 

a.i./acre). For cranberry and the small fruit vine climbing subgroup, the proposed maximum application 

rate is 0.22 lbs. a.i./acre (2 applications at 0.11 lbs. a.i./acre). The proposed application methods are 

aerial and ground foliar spray applications and chemigation techniques. The maximum proposed uses of 

indoxacarb can be found in Table 3. 
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Table 3. Application Information for the Proposed New Uses of Indoxacarb

Use Pattern Formula Application 

Method

PHI 

(days)

Applicatio

n Interval 

(days)

Maximum Single 

Application Rate 

(lbs. a.i./acre)

Maximum 

Number of 

Applications 

(season)

Seasonal Maximum 

Application Rate 

(lbs a.i./acre)

Beans

(Dry)

DuPontTM 

Avaunt®

Foliar 

Chemigation 7 7 0.11 4 0.44

Beans

(Snap)

DuPontTM 

Avaunt®

Foliar 

Chemigation 7 3 0.11 4 0.44

LowGrowing 

Berry

DuPontTM 

Avaunt®

Foliar 

Chemigation 30 7 0.11 4 0.44

Small Fruit 

Vine 

Climbing

DuPontTM 

Avaunt®

Foliar 

Chemigation 7 21 0.11 2 0.22

Beans (Dry) DuPontTM 

Steward®EC

Foliar 

Chemigation 7 7 0.11 4 0.44

2.3. Conceptual Model 

A. Risk hypothesis

The following risk hypothesis is being employed for this national-scale drinking water assessment:

Indoxacarb, when used in accordance with proposed labels, can result in off-site movement of the 

chemical through runoff after rain events, soil and possible wind erosion, and spray drift, leading 

to human exposure through consumption of contaminated drinking water. 

B. Conceptual model

The source of the stressor is the insect sodium channel blocker, indoxacarb. The mechanisms of release 

of indoxacarb are foliar aerial and ground applications, as well as through chemical irrigation systems 

(chemigation). Environmental transport of indoxacarb can occur through surface water runoff after rain 

events, soil and possible wind erosion and spray drift. Leaching into groundwater is not expected to be a 

major dissipation pathway based on submitted batch equilibrium, aged soil column leaching and 

terrestrial field dissipation studies which showed that indoxacarb having a low potential to leach. Surface 

water runoff from the areas of application is assumed to follow topography. Spray drift will follow the 

wind directions. Potential emission of volatile compounds is not considered as a viable release 

mechanism for indoxacarb, since volatilization is not expected to be a significant route of dissipation for 

this chemical because of the low vapor pressure and Henry’s Law constant of the compound. 

3. ANALYSIS

3.1. Environmental Fate and Transport Characterization

The proposed DupontTM Avaunt®insecticide contains 30% of active ingredient of (S) isomer of 

Indoxacarb which is formulated as a water dispersible granule formulation. In addition, the proposed 
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DupontTM Steward® EC insecticide contains 15.84% of active ingredient of (S) isomer of Indoxacarb

which is formulated as an emulsifiable concentrate. Most of the environmental fate studies were carried 

out with the either one of two older formulations: DPX-JW062 with a 50:50 (S: R) racemic mixture and 

DPX-MP062 with a 75:25 (S:R) racemic mixture. 

The following fate and transport characterization is for indoxacarb (parent) only. The half lives differ in 

Table 4 because of the total toxic residue (TTR) approach recommended by the MARC memorandum

(D267726). More information regarding the TTR approach including calculations can be found in the 

original assessment (USEPA 2000). 

The major routes of degradation for indoxacarb (DPX-JW062) are alkaline-catalyzed hydrolysis, 

photodegradation in water, and microbial mediated degradation. Appendix III summarizes indoxacarb’s 

degradation profile, including maximum percent formation. DPX-JW062 had abiotic hydrolysis halflives of 519 days in pH 5 buffer solution, 38 days in pH 7 buffer solution, and 1 day in pH 9 buffer 

solution (MRID 44477301). The major hydrolysis degradation product was IN-KT413 (48%). 

Additional abiotic hydrolysis data indicate indanone and trifluroromethoxyphenyl labeled DPX-MP062 

(3S: 1R ratio) had hydrolysis half-lives of 577.62 days in pH 5 buffer solution, 21.80 days in pH 7 buffer 

solution, and 1.11 days in pH 9 buffer solution (MRID 45795801). Major degradation products included 

IN-KT413 (88.1%) and IN-MF014 (14.7%). A supplementary hydrolysis study showed the enantiomeric 

ratio of the isomers of indoxacarb remained constant during the study. 

The photodegradation half-life for DPX-JW062 was 3.16 days in pH 5 buffer solution (MRID 44477302). 

Major degradation products included IN-KB687 (22.1%) and IN-MF014 (37.8%) for phenyl labeled 

DPX-JW062 and IN-MH304 (19.9%) and MW297 (14.1%) for indanone labeled indoxacarb. Additional 

aqueous photolysis data indicate DPX-MP062 had a environmental phototransformation half-life of 

approximately 5 days (MRID 45795802). Major photodegradation products were identified as INMH304 (32.3%), IN-CO639 (10.2%) and IN-MA573 (19.9%) for indanone labeled indoxacarb; and INMF014 (37.6 %), IN-KB687 (28.7%) for phenyl labeled indoxacarb. Additionally, numerous 

unidentified polar and non-polar degradation products were found for both labels of indoxacarb. A 

supplementary photodegradation study showed the enantiomeric ratio of the isomers of indoxacarb 

remained constant during the study. 

The extent of DPX-JW062 photodegradation on soil is questionable because there was extensive 

degradation in dark controls with similar degradation products (MRID 44477303). The dark control 

corrected half-life was 126 days. The major degradation product was IN-KB687 (22%).

DPX-JW062 degraded with half-lives ranging from 3 to 693 days in aerobic soil metabolism studies 

(MRIDs 44477304, 45166303, 457950803, 45795812, 45906701). Maximum formation rates for major 

degradates included IN-JT333 (18.6% - 45906701), IN-KG433 (39.7% - 45166303), IN-JU873 (12.9% -

45166303), IN-ML438 (9.7% - 45166303), IN-MK643 (12% - 45166303, 44477304), IN-MK638 (28.1% 

- 45166303), IN-ML 437OH (13% - 44477304), IN-KB687 (11% - 44477304), CO2 (35.73% - 45795803) 

and non-extractable residues (66.1% - 45906701).

DPX-JW062 degraded with half-lives ranging from 18 to 34 days in near-neutral aerobic aquatic

environments (MRID 44477306). Maximum formation rate for major degradates included IN-JT333 

(10.5% of applied, half-life of 54 days under aerobic soil conditions), Unknown A (24.1%), CO2 (19%) 

and non-extractable residues (38%). In addition, DP-MP062 degraded with total system half-lives of 30.7 

and 21.3 days in a pond water/sediment and lake water/sediment systems, respectively (MRID 

45793301). For the pond water/sediment system, maximum formation rates for major degradation 

products included IN-KT413 (42.1%), IN-MP819 (10.3%) and IN-MS775 (12.8%). In the lake 

water/sediment system, maximum formation rates for major degradation products included IN-JT333

(25.7%), IN-KT413 (31.4%) and CO2 (25.8%).
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DPX-JW062 degraded with half-lives of 147 and 231 days in anaerobic soil-water environments (MRID 

44477305). Maximum formation rate for major degradates included IN-JT333 (28.2% of applied), INKT413 (16.0%) and non-extractable residues (43%). In addition, DPX-JW062 degraded with total system 

half-lives of 192 and 315 days for the indanone and phenyl label indoxacarb, respectively, in a floodedsilt loam sediment system (MRID 45795804). Similarly, major degradates included IN-JT333 and INKT413 (16.0%). Enantiomeric ratios of the R and S isomers remained constant during the study.

Degradation products of indoxacarb had different half-lives in aerobic soils. IN-KT413 and IN-MK638 

were non-persistent (t1/2 1.3 to 16.2 days) in foreign and US mineral soils (MRID 45906703, 45795816). 

IN-KG433 and IN-JU873 were non-persistent to moderately persistent (t1/2 10.5 to 58.7 days) in aerobic 

soils (MRIDs 45795815 and 45795814). In contrast, IN-MK643 was persistent (t1/2 141.5 to 346.6 days) 

in aerobic soils (MRID 45795817). Degradation products except for CO2 were not identified. However, 

the degradation pathways were generally associated with oxidative mineralization to CO2 and residue 

incorporation into non-extractable soil organic matter. 

The results of batch equilibrium studies suggest low mobility of DPX-JW062 and IN-JT333 in terrestrial 

and aquatic environments. Reviewer calculated soil: water partition coefficients for DPX-JW062 are 29 

ml/g in Myaka sand soil, 30 ml/g in Donna sandy clay loam soil, 99 ml/g in Chino loam soil, and 40 ml/g 

in a Tama silt loam soil (MRIDs 44477308 and 45795809). Soil: water partition coefficients for INJT333 are 251 ml/g in Myaka sand soil, 115 ml/g in Donna sandy clay loam soil, 308 ml/g in Chino loam 

soil, and 147 ml/g in a Tama silt loam soil. There was no correlation between soil organic matter content 

and indoxacarb soil: water partitioning coefficients. The calculated Kds for indoxacarb degradation 

products (IN-KT413, IN-KG433, IN-MK638, and IN-MK643) ranged from 1.2 to 11.3 ml/g in five US 

and foreign mineral soils (MRIDs 45795808, 45906702, 45795807, 45795806). In contrast, the 

calculated Kds for IN-JU873 ranged from 52.1 to 406.4 (MRID 45795805). With an exception of INJU873, the batch equilibrium data suggest indoxacarb degradation products may exhibit some mobility in 

soil. Aged soil column leaching studies, however, indicate aged residues of DPX-MP062 have low 

mobility in packed soil columns (MRID 44477309).

Plant and soil volatility studies indicate that DPX-JW062 has low volatility from plant and soil surfaces, 

since after 168 hours of incubation, < 3% of applied radioactivity had volatilized from lettuce plants and 

soil surface (MRID 44491703). 

For DPX-JW062, at 10 and 100 ug/L concentrations, the calculated fish bioconcentration factors were

395 to 504X for edible tissues, 1568-2081X for nonedible tissues, and 1044-1351X for whole fish tissues, 

respectively (MRIDs 44477319 and 45805301). When based on residues of the active isomer, DPXKN128, maximum BCFs were 24 in fillet, 153 in viscera, and 90 in whole fish for the 10 ppb exposure. 

The major degradation product in fish tissues (>10% recovered) was IN-JT333. Minor degradation 

products (<10% recovered) were IN-ML811, IN-KT319, IN-KG433, and IN-JU873. The depuration halflife of bioaccumulated indoxacarb 14C residues ranged from 6.55 to 7.88 days.

For DPX-JW062 applied at 0.6 lbs ai/A on bare sand soil, the calculated field dissipation half-lives ranged

from 72 to 79 days in Florida and California, respectively (MRIDs 44477312, 44477315 and 44477316). 

Field studies on bare ground soils using radiolabeled DPX-JW062 and with 0.88 lb a.i./A application rate 

indicated field dissipation half-lives ranging from 29 to 113 days in Delaware and Texas and 73 to 119 

days in California and Florida, respectively (MRIDs 44477311 and 45850002 ). The degradate IN-JT333 

was detected in all field studies. The degradate IN-KG433 was only detected in the radiolabeled field 

studies. Some leaching of parent and residues occurred but were not detected below 45 cm (18 inches).
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3.2. Drinking Water Exposure Modeling

Estimated drinking water concentrations (EDWCs) were generated using EFED’s standard suite of 

models. Since there is no standard scenario to model berry, the specialty Oregon Berry OP scenario was 

utilized. In addition, the Provisional Cranberry Model was utilized to model cranberry. The maximum 

application rate for the proposed new uses was modeled. 

3.2.1. Models

Pesticide Root Zone Model (PRZM v3.12.2, May 12, 2005) and Exposure Analysis Modeling System 

(EXAMS v2.98.04.06, April 25, 2005) are simulation models coupled with the input PE5.pl shell (PE5, 

PE Version 5.0, November 15, 2006) to generate EDWCs of indoxacarb residues that may occur in 

surface water used as drinking water. The PRZM model simulates pesticide movement and 

transformation on and across the agricultural field resulting from crop applications. The EXAMS model 

simulates pesticide loading via runoff, erosion, and spray drift assuming a standard watershed of 172.8 ha 

that drains into an adjacent standard drinking water index reservoir of 5.26 ha, an average depth of 2.74 

m. A more detailed description of the index reservoir watershed can be found in Jones et al., 1998. The 

coupled PRZM/EXAMS model and users manuals may be downloaded from the U.S. Environmental 

Protection Agency (EPA) Water Models web-page (USEPA, 2011). Percent Crop Areas (PCA) that

account for the maximum area within a watershed that may be planted with the modeled crop are applied 

to concentrations predicted by PRZM/EXAMS.

Screening Concentration in Ground Water (SCI-GROW v2.3, Jul. 29, 2003) is a regression model used as 

a screening tool to estimate pesticide concentrations found in ground water used as drinking water. SCIGROW was developed by fitting a linear model to ground water concentrations with the Relative Index of 

Leaching Potential (RILP) as the independent variable. Ground water concentrations were taken from 90-

day average high concentrations from Prospective Ground Water studies. The RILP is a function of 

aerobic soil metabolism and the soil-water partition coefficient. The output of SCI-GROW represents the 

concentrations of residues that might be expected in shallow unconfined aquifers under sandy soils, which 

is representative of the ground water most vulnerable to pesticide contamination and likely to serve as a 

drinking water source. The SCI-GROW model and user’s manual may also be downloaded from the EPA 

Water Models web-page (USEPA, 2011). 

The Provisional Cranberry Model is a provisional refinement to and based on the same assumptions as the 

Tier I Rice Model (v1.0, May 8, 2007). Refinements include the addition of simple degradation processes 

in dry and flooded conditions and a water depth of twelve inches, rather than the water depth of four 

inches used in the rice model. These modifications allow estimation of screening-level peak and annual 

mean EDWCs of indoxacarb residues of concern that may occur in untreated surface water used as 

drinking water following use on cranberries. Degradation of indoxacarb residues of concern on dry 

cranberry bog soil is assumed to occur predominantly via aerobic microbial metabolism. Residue 

degradation in flooded bogs is assumed to occur via aerobic microbial metabolism in the water column 

and via anaerobic microbial metabolism in the sediment.

Cranberry bogs are not typically flooded until the night before harvesting. Because use of indoxacarb on 

cranberries is proposed for up to two applications, each seven days apart, with a thirty-day pre-harvest 

interval, the proposed single application rate (0.22 lbs a.i./A) was aged on dry soil with the Provisional 

Cranberry Model for two durations, applied at thirty seven and thirty days before harvest. The resulting 

residues (in lbs a.i./A) were then summed together and input used as for the flooded component of the 

model to estimate peak and annual mean EDWCs in bog tailwater following harvest.
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The cranberry bog water depth of twelve inches is a maximum depth recommended by the Cape Cod 

Cranberry Growers Association (2001). Previous assessments of mesotrione uses that employed the 

Provisional Cranberry Model assumed a water depth of eighteen inches (DP barcode 339984, USEPA, 

2004; DP barcode 325840, USEPA, 2006a), which is within the range of water depths traditionally used. 

However, modern water conservation pressures are causing cranberry growers to reduce the flood depth 

to fewer inches above the vertical cranberry branches, which grow up to eight inches high (Cape Cod 

Cranberry Growers Association, 2001; The Cranberry Institute, 2008). Therefore, a twelve-inch deep 

flood is a reasonable refinement to model assumptions. The equations used in the Provisional Cranberry 

Model are briefly described in Appendix II. 

3.2.2. Input Parameters

For dry and snap beans and low growing berries, the maximum application rate (4 applications at 0.11 lbs. 

a.i./acre) was modeled to capture the maximum EDWCs. In addition, the maximum application rate (2

applications at 0.11 lbs. a.i./acre) was modeled for cranberries and the small fruit vine climbing subgroup. 

Foliar (aerial and ground) spray applications and chemigation methods were modeled for these maximum 

use rates. 

Application timing was based on the crop scenario’s harvest date, pre-harvest interval (PHI), application 

interval and total number of applications. Chemical property input values were chosen according to the 

current input parameter guidance (USEPA, 2009). Standard PCAs were used for all uses as estimates of 

the extent of watershed on which crops are grown (Effland et al., 1999). The default agricultural PCA of 

0.87 was used for the proposed new uses because they are not confined to specific regions of the U.S. 

Actual fractions of cropped areas could be less in some areas of the country. 

Input parameters and explanations for the PRZM/EXAMS and SCI-GROW and Provisional Cranberry 

models are listed in Table 4, Table 5, and Table 6, respectively. 

Table 4. PRZM/EXAMS Input Parameters for Indoxacarb

Input Parameter: Value: Comment: Source:

Scenario(s): Beans (Dry and Snap): 

MI Bean

Low Growing Berry: 

OR Berry

Cranberry

Small Fruit Vine Climbing: 

NY Grape

representative scenarios for each use EFED Scenarios

Maximum Single 

Application Rate

lbs a.i./acre (kg a.i./ha)

All proposed uses: 

0.11 (0.124)

proposed rate Proposed labels

Applications per Year Beans (Dry and Snap): 

4

Low Growing Berry: 

OR Berry: 4

Cranberry: 2

Small Fruit Vine Climbing: 

2

Label directions. Label specifies rates per 

crop. If there are multiple crops grown per 

year, yearly rates may be higher. 

Proposed labels
Page 10 of 25

Table 4. PRZM/EXAMS Input Parameters for Indoxacarb

Input Parameter: Value: Comment: Source:

Application Interval (days) Beans (Dry and Snap): 7

Low Growing Berry: 7

Small Fruit Vine Climbing: 21

Label directions Proposed labels

Date of Initial Application

(scenario: day-month)

Bean (Dry): 

MI Bean: 07-08

Bean (Snap): 

MI Bean: 11-08

Low Growing Berry: 

OR Berry: 09-06

Small Fruit Vine Climbing: 

NY Grape: 17-09

For all crops, the date of initial application was 

calculated from the harvest date from the crop 

profile and the Pre-Harvest Interval (PHI) and 

number and interval of applications from the 

proposed label.

Crop Scenarios and 

proposed labels

Application Method Aerial (foliar)

Ground (foliar)

Chemigation

label directions Proposed labels

CAM Input 2 (foliar: aerial and ground)

1 (chemigation)

(1) Soil applied, default incorporation depth, 

linearly decreasing with depth (2) linear foliar 

based on crop canopy

US EPA, 2005

IPSCND Input Beans (Dry and Snap): 2

Low Growing Berry: 3

Small Fruit Vine Climbing: 3

...remaining pesticide on foliage is (1) 

converted to surface application to the top soil 

layer, (2) completely removed after harvest, (3) 

is retained as surface residue and continues to 

decay.

US EPA, 2005

Spray Drift Fraction 0.16 (aerial)

0.064 (ground)

0 (chemigation)

-- Input parameter guidance 

(USEPA, 2009) 

Application Efficiency 0.95 (aerial)

0.99 (ground)

1.0 (chemigation)

-- Input parameter guidance 

(USEPA, 2009)

Molecular Mass (g/mol) 527.8 -- Product Chemistry

Vapor Pressure at 25°C 

(torr)

1.9 x 10-10-- Product Chemistry

Henry’s Law Constant

(atm-m

3

/mol)

1.6 x 10-10-- Calculated from water 

solubility, vapor pressure 

and molecular weight

Solubility in Water (mg/L) 0.8 pH 7 at 20°C Product Chemistry

Organic Carbon Partition 

Coefficient (KOC) (L/kgOC)

400 Since this assessment is based on cumulative 

residues, the mean value for IN-KG433 was 

used because it has the lowest non-sand Kf and 

Koc of the residues of toxicological concern

MRID 45795806

Aerobic Soil Metabolism 

Half-life (days)

267 Rate Constant = 0.0026/day. Linear fitting 

techniques using the first order degradation 

model provided a poor description of the data 

as shown by non-significant F tests and R

2

. 

Therefore, nonlinear fitting techniques with the 

first order decay model were used to estimate 

rate constants for indoxacarb residue 

degradation.

MRID 44477304

MRID 44477307
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Table 4. PRZM/EXAMS Input Parameters for Indoxacarb

Input Parameter: Value: Comment: Source:

Aerobic Aquatic 

Metabolism Half-life (days)

71 Rate Constant = 4.0 x 10-4/hour. Non-linear 

fitting techniques were utilized as described in

ASM above.

MRID 44477306

Anaerobic Aquatic 

Metabolism Half-life (days)

577 Rate Constant = 5.0 x 10-5/hour. Non-linear 

fitting techniques were utilized as described in 

ASM above.

MRID 44477305

Hydrolysis Half-lives (days) 0 (stable) Rate Constant = 1.5 x 10-4/hour. Non-linear 

fitting techniques were utilized as described in 

ASM above.

MRID 44477301

Aqueous Photolysis

Half-life (days)

0 (stable) -- MRID 44477302

Table 5. SCI-GROW Input Parameters for Indoxacarb

Input Parameter Value Comment Source

Maximum Single Application 

Rate per growing season (lbs 

a.i./A)

0.11 maximum single application rate Proposed labels

Applications per Year 4 (beans, 

berries)

label directions Proposed labels

Organic Carbon Partition 

Coefficient (KOC) (L/kgOC)

360 1 median value of IN-KG433 degradate data 

because there was not a greater than a threefold variation among five values

MRID 45795806

Aerobic Soil Metabolism

Half-life (days)

267 2 Rate Constant = 0.0026/day. MRID 44477304

MRID 44477307

1

= Individual Koc values for the degradate IN-KG433 (518, 360, 433, 348, 343).

2

= Linear fitting techniques using the first order degradation model provided a poor description of the data as shown 

by non-significant F tests and R

2

. Therefore, nonlinear fitting techniques with the first order decay model were used 

to estimate rate constants for idoxacarb residue degradation.

Table 6. Provisional Tier 1 Cranberry Model Input Parameters for Indoxacarb

Input Parameter Value Source

Application Rate (lbs a.i./A) 0.11 Proposed label

Applications per Year 2 Proposed label

Organic Carbon Partition Coefficient (KOC) (L/kgOC) 400 Represents the mean value for IN-KG433

Aerobic Soil Metabolism Half-life (days) 267 Rate Constant = 0.0026/day

Aerobic Aquatic Metabolism Half-life (days) 71 Rate Constant = 4.0 x 10-4/hour

Anaerobic Aquatic Metabolism Half-life (days) 577 Rate Constant = 5.0 x 10-5/hour

3.2.3. Modeling Results

The maximum use patterns were modeled to yield the maximum EDWCs for surface water and 

groundwater (Table 7). The recommended maximum EDWC concentrations are as follows. For surface 

water, cranberry yielded the highest EDWCs. The 1-in-10 yr annual peak (acute) concentration was 

59.26 μg/L, the 1-in-10 yr annual mean (chronic) concentration was 18.48 μg/L and the 30-year annual 

mean (cancer chronic) concentration was 18.48 μg/L. For groundwater, based on the proposed highest 

annual use rate for beans and berries, the SCI-GROW model estimated the indoxacarb concentration at 
Page 12 of 25

0.33 μg/L. Since these values are greater than the previous established EDWCs for cotton (D293793, 

D355124), they will supersede all previous EDWCs generated for indoxacarb.

Representative PRZM/EXAMS, SCI-GROW and Cranberry model outputs with input parameter data are 

attached in Appendix I.

Table 7. Indoxacarb Estimated Drinking Water Concentrations (EDWCs)1for Surface 

Water and Ground Water based on selected Crop Scenarios

Proposed

Label Use

PRZM/EXAMS

Scenario1

(first app date)

Method2

Maximum 

Application Rate

(interval between 

applications)

1-in-10 

year 

acute 

(μg/L)

1-in-10 

year 

chronic 

(μg/L)

30- year 

average 

(μg/L)

DuPontTM Avaunt®and Steward® EC Insecticides

Surface Water

Beans 

(Dry) MI Bean

(August 7)

A

4 app @ 0.11 lb a.i./acre

(7 days)

18.68 6.03 3.50

G 18.50 5.81 3.18

C 17.01 5.40 3.13

Beans 

(Snap) MI Bean

(August 11)

A

4 app @ 0.11 lb a.i./acre

(7 days)

18.90 5.77 3.14

G 18.38 5.53 2.80

C 15.74 4.92 3.10

Low 

Growing 

Berry

(including 

Cranberry)

OR Berry3

(June 9)

A

4 app @ 0.11 lb a.i./acre

(7 days)

4.19 1.97 1.54

G 3.55 1.53 1.10

C 3.03 1.16 0.74

Provisional Cranberry 

Model --

2 app @ 0.11 lb a.i./acre

(7 days) 59.26 18.48 18.48

Small Fruit 

Vine 

Climbing 

Subgroup

NY Grape

(September 17)

A

2 app @ 0.11 lb a.i./acre

(21 days)

4.49 1.86 1.32

G 3.94 1.60 1.04

C 3.16 1.21 0.75

Ground Water

SCIGROWBean

Berry -- 4 app @ 0.11 lb a.i./acre 0.33 0.33 0.33

1 For surface water (PRZM/EXAMS), EDWC values adjusted with a Percent Cropped Area (PCA) factor of 0.87. 

For ground water (SCI-GROW), no PCA adjustment was utilized. Bold numbers denote maximum EDWC values.

2 A = aerial application, G = ground application, C = chemigation.

3

Since there is no standard scenario to model berry, the specialty Oregon Berry OP scenario was utilized.

3.2.4. Monitoring Data

There was no surface water or groundwater monitoring data available; therefore, the surface water and 

ground water assessment was based solely on the PRZM/EXAMS, SCI-GROW and Provisional 

Cranberry modeling, respectively. 

3.2.5 Drinking Water Treatment

There is no available information on the drinking water treatment effects on indoxacarb.
Page 13 of 25

4. Uncertainties, Assumptions and Limitations

1.) A major uncertainty in the assessment is the lack of environmental fate data for the toxic 

transformation products of DPX-JW062 (Indoxacarb). In order to address this uncertainty, 

EFED has conducted the Tier II modeling on the summed DPX-JW062 residues instead of 

individual residues. This approach was taken because the environmental fate studies were 

deficient in addressing the identification and fate of DPX-JW062 transformation products in 

the tolerance expression. In cases where the environmental fate data did not adequately 

identify DPX-JW062 residues such as the aerobic aquatic and anaerobic aquatic studies, the

half-lives were calculated on cumulative residues rather than the summation of toxic DPXJW062 residues. 

2.) The cumulative residue modeling method assumes environmental fate properties for 

indoxacarb and its degradation products (IN-JT333, IN-KG4333, IN-KT413, IN-ML437-0H) 

are similar. This modeling approach provides a conservative assessment process for 

consideration of simultaneous formation and decline of indoxacarb residues. 

3.) Indoxacarb degradation can be characterized as a “hockey stick” behavior with a rapid 

degradation rate followed by a slower degradation rate. Selection of a suitable soil 

degradation half-life is difficult due the large discrepancy of half-lives estimated using 

linearized first-order degradation model and 2 parameter exponential decay model.

4.) Other uncertainties in the modeling are associated with the selection of the most 

representative model for describing DPX-JW062 residue degradation. Linear fitting 

techniques using the first order degradation model (ln(y/a)=-bt) provided a poor description 

of the aerobic soil metabolism data as shown by non-significant F tests and low coefficients 

of determination (R2). Therefore, nonlinear fitting techniques (as employed through 

Sigmaplot-Regression Wizard) with the first order decay model (y=ae -bx) were used to 

estimate rate constants for DPX-JW062 residue degradation. This fitting procedure was used 

to estimate the degradation rate constants for hydrolysis, aerobic soil metabolism, aerobic 

aquatic metabolism, and anaerobic aquatic metabolism. 

5.) The lowest adsorption Koc coefficient of the toxic DPX-JW062 residues (IN-KG433) was 

used to represent sorption in soil and aquatic environments. 

6.) The proposed label specifies rates per crop. If there are multiple crops grown per year, the 

yearly rate may be higher resulting in underestimation of risk if the proposed commodities 

are grown more than one crop per year. 

7.) In general, the likelihood that multiple crops from the list of proposed uses will be found 

within a single watershed where indoxacarb is used is unknown; therefore, the default Percent 

Crop Area (PCA) of 0.87 was utilized. 
Page 14 of 25

5. Conclusions:

The Tier II drinking water exposure estimates are based on the indoxacarb proposed new uses represented 

by the maximum use patterns based on the proposed label. Review of the surface water and groundwater

data, the Provisional Cranberry Model yielded the maximum EDWCs in this assessment. The 1-in-10 yr 

annual peak (acute) concentration was 59.26 μg/L, the 1-in-10 yr annual mean (chronic) concentration 

was 18.48 μg/L and the 30-year annual mean (cancer chronic) concentration was 18.48 μg/L. For 

groundwater, based on the proposed highest annual use rate representing beans and berries, the SCIGROW model estimated the indoxacarb concentration at 0.33 μg/L. 

The estimated drinking water concentrations generated in this assessment supersede all other values for 

indoxacarb since they represent the highest concentrations to date.
Page 15 of 25

REFERENCES

Cape Cod Cranberry Growers Association. 2001. Cranberry Water Use: An Information Fact Sheet. 

June, 2001. Online at: http://www.cranberries.org/pdf/wateruse.pdf

Effland, W. R., N. C. Thurman, I. Kennedy. 1999. Proposed Methods for Determining Watershedderived Percent Crop Areas and Considerations for Applying Crop Area Adjustments to Surface 

Water Screening Models. Presentation to the FIFRA Science Advisory Panel, May 27, 1999. 

The Cranberry Institute. 2008. About Cranberries. 2003-2008. Online at: 

http://www.cranberryinstitute.org/about_cranberry.htm

Jones, R. D., S. Abel, W. R. Effland, R. Matzner, R. Parker. 1998. An Index Reservoir for Use in 

Assessing Drinking Water Exposure. Proposed Methods for Basin-scale Estimation of Pesticide 

Concentrations in Flowing Water and Reservoirs for Tolerance Reassessment. Presentation to 

FIFRA Science Advisory Panel, June 29-30, 1998. 

USEPA 2000. Index Reservoir Drinking Water Assessment for DPX-JW062 {(R,S)-methyl-7-chloro2,5-dihydro-2-[(methylcarbonyl)[4-(trifluoromethoxy) phenyl] amino]carbonyl]indeno[1,2-

e][1,3,4]oxadiazine-4a(3H)-carboxylate} and its Transformation Products. DP 267726. 

USEPA. 2004. Wolf, J. Section 18 Request for Use of Mesotrione on Cranberry in Oregon and 

Washington. DP Barcode D339984. EFED memorandum to RD. Undated.

USEPA. 2006. Standardized Soil Mobility Classification Guidance. U.S. Environmental Protection 

Agency, Office of Prevention, Pesticides and Toxic Substances, Office of Pesticide Programs, 

Environmental Fate and Effects Division, Memorandum. April 21, 2006.

USEPA. 2009. Guidance for Selecting Input Parameters in Modeling the Environmental Fate and 

Transport of Pesticides, Version 2.1. U.S. Environmental Protection Agency, Office of Chemical 

Safety and Pollution Prevention, Office of Pesticide Programs, Environmental Fate and Effects 

Division, October 22, 2009. 

USEPA. 2011. Water Models. U.S. Environmental Protection Agency, Pesticides: Science and Policy. 

Last updated: June 30, 2011. Online at: http://www.epa.gov/oppefed1/models/water/
Page 16 of 25

Appendix I:

Model Outputs: PRZM/EXAMS, SCI-GROW, Cranberry
Page 17 of 25

Representative PRZM/EXAM Output: Michigan Bean – Aerial Application

stored as SnapBeanA.out

Chemical: Idoxacarb

PRZM environment: MIbeansSTD.txt modified Tueday, 29 May 2007 at 13:56:44

EXAMS environment: ir298.exv modified Tueday, 26 August 2008 at 06:14:07

Metfile: w14826.dvf modified Tueday, 26 August 2008 at 06:15:04

Water segment concentrations (ppb)

Year Peak 96 hr 21 Day 60 Day 90 Day Yearly

1961 10.40 10.09 9.37 8.62 8.09 2.73

1962 5.08 5.01 4.75 4.32 4.09 3.05

1963 3.49 3.40 3.21 2.96 2.69 1.80

1964 4.62 4.51 4.10 3.56 3.32 1.94

1965 8.09 7.88 7.46 6.89 6.22 3.20

1966 4.53 4.42 4.03 3.62 3.56 2.78

1967 5.46 5.37 5.12 4.66 4.60 2.95

1968 8.42 8.22 7.98 6.93 6.20 3.67

1969 4.47 4.41 4.21 3.95 3.67 2.48

1970 7.63 7.46 6.91 6.49 6.12 2.61

1971 4.36 4.30 4.07 3.67 3.46 2.77

1972 7.31 7.17 6.82 6.19 5.99 3.36

1973 5.22 5.09 4.69 4.22 4.26 3.12

1974 4.48 4.39 4.10 3.76 3.63 2.67

1975 23.37 23.05 21.26 18.45 16.62 6.71

1976 9.64 9.52 9.02 8.16 7.61 4.56

1977 6.02 5.89 5.55 4.83 4.55 2.40

1978 5.27 5.18 4.80 4.07 3.71 2.44

1979 3.09 3.01 2.71 2.34 2.19 1.72

1980 8.59 8.36 7.65 6.50 5.90 2.50

1981 15.97 15.62 14.44 12.44 11.69 5.23

1982 7.72 7.64 7.26 6.50 6.07 4.77

1983 6.71 6.53 5.97 5.52 5.15 3.36

1984 4.58 4.47 4.14 3.91 3.82 2.60

1985 22.36 21.75 19.76 16.77 15.05 6.02

1986 23.32 22.79 21.51 18.92 17.44 8.62

1987 13.12 12.79 11.86 10.06 9.18 6.71

1988 7.06 6.88 6.37 5.92 5.71 4.12

1989 11.22 10.93 9.91 8.27 7.53 4.03

1990 5.41 5.30 4.92 4.78 4.65 3.50

Sorted results

Prob. Peak 96 hr 21 Day 60 Day 90 Day Yearly

0.03 23.37 23.05 21.51 18.92 17.44 8.62

0.06 23.32 22.79 21.26 18.45 16.62 6.71

0.10 22.36 21.75 19.76 16.77 15.05 6.71

0.13 15.97 15.62 14.44 12.44 11.69 6.02

0.16 13.12 12.79 11.86 10.06 9.18 5.23

0.19 11.22 10.93 9.91 8.62 8.09 4.77

0.23 10.40 10.09 9.37 8.27 7.61 4.56

0.26 9.64 9.52 9.02 8.16 7.53 4.12

0.29 8.59 8.36 7.98 6.93 6.22 4.03

0.32 8.42 8.22 7.65 6.89 6.20 3.67

0.35 8.09 7.88 7.46 6.50 6.12 3.50

0.39 7.72 7.64 7.26 6.50 6.07 3.36

0.42 7.63 7.46 6.91 6.49 5.99 3.36

0.45 7.31 7.17 6.82 6.19 5.90 3.20

0.48 7.06 6.88 6.37 5.92 5.71 3.12

0.52 6.71 6.53 5.97 5.52 5.15 3.05

0.55 6.02 5.89 5.55 4.83 4.65 2.95

0.58 5.46 5.37 5.12 4.78 4.60 2.78

0.61 5.41 5.30 4.92 4.66 4.55 2.77

0.65 5.27 5.18 4.80 4.32 4.26 2.73

0.68 5.22 5.09 4.75 4.22 4.09 2.67

0.71 5.08 5.01 4.69 4.07 3.82 2.61

0.74 4.62 4.51 4.21 3.95 3.71 2.60

0.77 4.58 4.47 4.14 3.91 3.67 2.50

0.81 4.53 4.42 4.10 3.76 3.63 2.48

0.84 4.48 4.41 4.10 3.67 3.56 2.44

0.87 4.47 4.39 4.07 3.62 3.46 2.40

0.90 4.36 4.30 4.03 3.56 3.32 1.94

0.94 3.49 3.40 3.21 2.96 2.69 1.80

0.97 3.09 3.01 2.71 2.34 2.19 1.72

0.10 21.72 21.14 19.23 16.34 14.71 6.64 5.77

18.90 Average of yearly averages: 3.61 3.14

Inputs generated by pe5.pl - Novemeber 2006

Data used for this run:

Output File: SnapBeanA

Metfile: w14826.dvf

PRZM scenario: MIbeansSTD.txt

EXAMS environment file: ir298.exv

Chemical Name: Idoxacarb

Description Variable NameValue Units Comments

Molecular weight mwt 527.8 g/mol

Henry's Law Const. henry 1.60E-10 atm-m^3/mol

Vapor Pressure vapr 1.90E-10 torr

Solubility sol 0.8 mg/L

Kd Kd mg/L

Koc Koc 400 mg/L

Photolysis half-life kdp 0 days Half-life

Aerobic Aquatic Metabolism kbacw 71 days Halfife

Anaerobic Aquatic Metabolism kbacs 577 days Halfife

Aerobic Soil Metabolism asm 267 days Halfife

Hydrolysis: pH 7 0 days Half-life

Method: CAM 2 integer See PRZM manual

Incorporation Depth: DEPI cm

Application Rate: TAPP 0.124 kg/ha

Application Efficiency: APPEFF 0.95 fraction

Spray Drift DRFT 0.16 fraction of application rate applied to pond

Application Date Date 8-Nov dd/mm or dd/mmm or dd-mm or dd-mmm

Interval 1 interval 7 days Set to 0 or delete line for single app.

app. rate 1 apprate 0.124 kg/ha

Interval 2 interval 7 days Set to 0 or delete line for single app.

app. rate 2 apprate 0.124 kg/ha

Interval 3 interval 7 days Set to 0 or delete line for single app.

app. rate 3 apprate 0.124 kg/ha

Record 17: FILTRA

IPSCND 2

UPTKF

Record 18: PLVKRT

PLDKRT

FEXTRC 0.5

Flag for Index Res. Run IR Reservoir

Flag for runoff calc. RUNOFF total none, monthly or total(average of entire run)
Page 18 of 25

SCI-GROW Output:

SCIGROW

VERSION 2.3

ENVIRONMENTAL FATE AND EFFECTS DIVISION

OFFICE OF PESTICIDE PROGRAMS

U.S. ENVIRONMENTAL PROTECTION AGENCY

SCREENING MODEL

FOR AQUATIC PESTICIDE EXPOSURE

SciGrow version 2.3

chemical:Idoxacarb

time is 10/10/2012 23:40:11

------------------------------------------------------------------------

 Application Number of Total Use Koc Soil Aerobic

 rate (lb/acre) applications (lb/acre/yr) (ml/g) metabolism (days)

------------------------------------------------------------------------

 0.110 4.0 0.440 3.60E+02 267.0

------------------------------------------------------------------------

Groundwater screening cond (ppb) = 3.34E-01 or 0.33 ug/L

************************************************************************

Provisional Cranberry Output:

Provisional Cranberry Model Equations: EEC = EEC 0 * exp (-day * (dw * AAM t1/2) + (dsed * θ * AnAM t1/2) + (dsed * ρ * Kd * AnAM t1/2) / (dw + dsed * (θ + ρ * Kd))))

EEC 0 = App rate * 100 / (dw + (dsed * (θ + (ρ * Kd / 1000))))

Inputs Model Parameters Calculated Parameters Exposure Water Peak 21-d Mean60-d Mean

Parameter Value Parameter Value Parameter Value Eco Paddy

Application rate (lbs/A) 0.22 Water column depth (m) 0.305 App. rate (kg/ha) 0.24662 Eco 7-d Tail

Koc (L/kg) 400 Sediment depth (m) 0.01 Kd input (L/kg) 4 Peak Annual Mean

If no Koc, enter Kd (L/kg) Organic fraction of sediment 0.01 AAM rate k (1/d) 0.009763 DW (raw) 7-d Tail 68 21

Aer aq metabolism t1/2 (d) 71 Sediment bulk density (kg/m3) 1300 AnAM rate k (1/d) 0.001201 87% PCA 59.26 18.48

Anaer aq metabolism t1/2 (d) 577 Sediment porosity 0.509 ASM rate k (1/d) 0.002596 77% PCA (R4) 52 16

Aer soil metabolism t1/2 (d) 267 63% PCA (R17) 43 13

*Water column depth is 12 inches (0.305 m) to 18 inches (0.457 m).. 46% PCA (R2) 31 10

14% PCA (R1) 9.5 3.0

App rate, 37 d (lbs/A) = 0.11 Pre-PCA Values

App rate, 30 d (lbs/A) = 0.11 68.11 Peak EEC

Total lbs/A at harvest = 0.22 21.24 Annual Mean Tailwater EDWC
Page 19 of 25

Appendix II: Provisional Cranberry Model Equations

The Provisional Cranberry Model is a refinement of the Tier I Rice Model v1.0 (Equations 1 and 

2), which is a simple equilibrium partitioning equation that calculates a single, screening-level 

concentration in rice paddy water and released tailwater based on a compound’s application rate 

and soil mobility.

Equations 1-2: Tier I Rice Model v1.0 (USEPA, 2007b).

  w sed sed b d

ai

w

d d K

m

C

 

3

2

0

10

10 '



 

 (1)

and, if appropriate:

Kd 01KOC  0. (2)

where,

Cw0 = initial water concentration [μg/L]

mai' = mass applied per unit area [kg/ha]

Kd = water-sediment partitioning coefficient [L/kg]

KOC = organic carbon partitioning coefficient [L/kg]

dw = water column depth = 0.10 m

dsed = sediment depth = 0.01 m

θsed = porosity of sediment = 0.509

ρb = bulk density of sediment = 1300 kg/m3

First, the Tier I Rice Model was provisionally modified (Equation 3) to include as inputs 

degradation rate constants in order to estimate single, screening-level concentrations in paddy 

water or tailwater at a given time after application.

Equation 3: Provisional Modified Rice Model (Jones, 2006).

     

 

t

d d K

d k d k d K k

w w

w sed sed b d

w sed sed sed b d

C C e

















 

 







 

3

3

1 2 3

10

10

0

 

 

(3)

where,

Cw = water concentration [μg/L]

t = interval since last application [d]

k1 = upper 90th percentile rate constant in water column [1/d]

k2 = upper 90th percentile rate constant in pore water [1/d]

k3 = upper 90th percentile rate constant for adsorbed residues [1/d]

Then, the Provisional Modified Rice Model water column depth was lengthened to a depth that is 

used to flood cranberry bogs (i.e., 12 inches; Cape Cod Cranberry Growers Association, 2001).

i.e.,

dw = water column depth = 0.305 m
Page 20 of 25

In order to model degradation prior to the flood at harvest, the application rates for n number of 

pre-harvest applications were independently degraded over the interim until flooding and then 

summed (Equation 4).

Equation 4: Degradation in a Dry Bog.





 

n

k t

ai ai n

n m m e

1

4

' ' (4)

where,

mai' = mass per unit area at flood [kg/ha]

mai'n = mass applied per unit area on the nth application [kg/ha]

k4 = upper 90th percentile rate constant on dry bog [1/d]

tn = interval from the nth application to harvest [d]

n = number of pre-harvest applications

The following four equations and parameter sets constitute the Provisional Cranberry Model 

(Equations 1-4).

Equations 1-4: Provisional Cranberry Model.

  w sed sed b d

ai

w

d d K

m

C

 

3

2

0

10

10 '



 

 (1)

and, if appropriate:

Kd 01KOC  0. (2)

where,

Cw0 = initial water concentration [μg/L]

Kd = water-sediment partitioning coefficient [L/kg]

KOC = organic carbon partitioning coefficient [L/kg]

dw = water column depth = 0.305 m

dsed = sediment depth = 0.01 m

θsed = porosity of sediment = 0.509

ρb = bulk density of sediment = 1300 kg/m3

and, lastly:

     

 

t

d d K

d k d k d K k

w w

w sed sed b d

w sed sed sed b d

C C e

















 

 







 

3

3

1 2 3

10

10

0

 

 

(3)

where,

Cw = water concentration [μg/L]

t = interval since flood [d]

k1 = upper 90th percentile rate constant in water column [1/d]

k2 = upper 90th percentile rate constant in pore water [1/d]

k3 = upper 90th percentile rate constant for adsorbed residues [1/d]
Page 21 of 25

Appendix III: Indoxacarb’s Degradation Profile

Code Name/ 

Synonym Chemical Name Chemical Structure Study Type MRID

Maximum 

Formation

(% Applied)

IN-KT413 CAS Name: 

sodium 7-chloro-2,5,-dihydro-2-

[[(methoxycarbonyl)[4-

(trifluoromethoxy)phenyl]amino]car

bonyl]indeno[1,2-

e][l,3,4]oxadiazine-4a(3H)-

carboxylic acid

Molecular Weight: 513.82 g/mol 

(free acid) 

Hydrolysis 44477301 48.0

Hydrolysis pH 7

45795801 47.1

Hydrolysis pH 9 88.1

Aerobic Aquatic Metabolism 45793301 42.1

Anaerobic Aquatic Metabolism 44477305 16.0

IN-MF014 CAS Name: 

methyl 2-[[[4-

(trifluoromethoxy)phenyl]

amino ]carbonyl]hydrazine 

carboxylate

Hydrolysis pH 5

45795801

6.1

Hydrolysis pH 7 14.7

Aqueous Photolysis 44477302 37.8

Aqueous Photolysis 45795802 37.6

IN-MH304 CAS Name: 

Not Reported

Aqueous Photolysis 44477302 19.9
Page 22 of 25

Appendix III: Indoxacarb’s Degradation Profile

Code Name/ 

Synonym Chemical Name Chemical Structure Study Type MRID

Maximum 

Formation

(% Applied)

Aqueous Photolysis 45795802 32.3

MW 297 CAS Name: 

Not Reported

Proposed structure; not proven due to inability 

to synthesize standard

Aqueous Photolysis 44477302 14.1

IN-KB687 CAS Name: 

methyl[4(trifluoromethoxy)phenyl]c

arbamate

Molecular Weight: 235.16 g/mol

 

Aqueous Photolysis 44477302 22.1

Aqueous Photolysis 45795802 28.7

Soil Photolysis 44477303 22.0

Aerobic Soil Metabolism 44477304 11.0

IN-C0639 CAS Name: 

4-chloro-1,2-benzenedicarboxylic 

acid

Aqueous Photolysis 45795802 10.2

IN-MA573 CAS Name: 

2-carboxy-5-chloro benzeneacetic 

acid

Aqueous Photolysis 45795802 19.9

IN-JT333 CAS Name: 

methyl-7-chloro-2,5-dihydro -2-

[[[4(trifluoromethoxy)phenyl]amino

]carbonyl]indeno[1,2e][1,3,4]oxadia

zine -4a(3H)-carboxylate

Aerobic Soil Metabolism 45906701 18.6

Aerobic Aquatic Metabolism 44477306 10.5
Page 23 of 25

Appendix III: Indoxacarb’s Degradation Profile

Code Name/ 

Synonym Chemical Name Chemical Structure Study Type MRID

Maximum 

Formation

(% Applied)

Molecular Weight: 469.81 g/mol

Aerobic Aquatic Metabolism 45793301 25.7

Anaerobic Aquatic Metabolism 44477305 28.2

IN-KG433 CAS Name: 

Methyl-5-chloro-2,3-dihydro-2-

hydroxy-1[[[(methoxycarbonyl)[4-

(trifluoromethoxy)phenyl]amino]car

bonyl]hydrazono]-1H-indene-2-

carboxylate

Molecular Weight: 515.83 g/mol

Aerobic Soil Metabolism 45166303 39.7

IN-JU873 CAS Name: 

1-[[[[4-(trifluoromethoxy)phenyl] 

amino] carbonyl]hydrazono]-1Hindene-2-carboxylate

Molecular Weight: 457.8 g/mol

Aerobic Soil Metabolism 45166303 12.9
Page 24 of 25

Appendix III: Indoxacarb’s Degradation Profile

Code Name/ 

Synonym Chemical Name Chemical Structure Study Type MRID

Maximum 

Formation

(% Applied)

IN-ML438 CAS Name: 

7-chloro-2,4-dihydro-4-[4-4 -

(trifluoromethoxy)phenyl]-3Hindeno[2,1-e]-1,2,4-triazin-3-one

Molecular Weight: 379 g/mol

Aerobic Soil Metabolism 45166303 9.7

IN-MK643 CAS Name: 

l,2-dihydro-5-(trifluoromethoxy)-

2H-benzimidazol-2-one

Molecular Weight: 218.14 g/mol

Aerobic Soil Metabolism 45166303

44477304

12.0

IN-MK638 CAS Name: 

[4-(trifluoromethoxy)phenyl)urea

Molecular Weight: 220 g/mol

Aerobic Soil Metabolism 45166303 28.1

IN-ML437-

OH

CAS Name: 

Not Reported

Aerobic Soil Metabolism 44477304 13.0
Page 25 of 25

Appendix III: Indoxacarb’s Degradation Profile

Code Name/ 

Synonym Chemical Name Chemical Structure Study Type MRID

Maximum 

Formation

(% Applied)

IN-MP819 CAS Name: 

lndenol[1 ,2-e][1 ,3,4]oxadlazine-1 

(2H)-carboxylic acid, 7-chloro-3,5-

dlhydno-2-[[[4-

(triftuoromethoxy)phenyl]amino]car

bonyl]-, methyl ester

Molecular Weight: 469.8 g/mol

Aerobic Aquatic Metabolism 45793301 10.3

IN-MS775 CAS Name: 

7-Chloro-4a,5-dihydro-N-(4-

(trifluoromethoxy)phenyl]idenol[1 

,2-e][1 ,3,4]oxadiazine-2(3H)-

carboxamide

Molecular Weight: 411.8 g/mol

Aerobic Aquatic Metabolism 45793301 12.8

Unknown A Unidentified Aerobic Aquatic Metabolism 44477306 24.1

CO2

Carbon Dioxide O=C=O

Aerobic Soil Metabolism 45795803 35.7

Aerobic Aquatic Metabolism 44477306 19.0

Aerobic Aquatic Metabolism 45793301 25.8

Unextractable

Residues

Aerobic Soil Metabolism 45906701 66.1

Aerobic Aquatic Metabolism 44477306 38.0

Anaerobic Aquatic Metabolism 44477305 46.8